The running performance and estimated energy cost of hurling specific small-sided games

The current study examined the extent to which pitch dimensions can influence the physical and estimated energetic demands of hurling small-sided games. Training data ( n = 990) were collected from 24 (age 25.5 ± 3.2 years; height 178.9 ± 3.2 cm; body mass 78.5 ± 4.5 kg) hurling players using 4-Hz global positioning system technology (VX Sport, Lower Hutt, New Zealand). Total distance (m), high-speed running distance (m; ≥ 17 km/h), very high-speed running distance (m; ≥ 22 km/h), total accelerations ( n), acceleration distance (m), peak and mean velocity (km/h) were considered. In addition changes in velocity were analysed by assessing the acceleration actions during SSG. This allowed for the assessment of estimated energy expenditure (kJ/kg) and the equivalent distance covered a different metabolic power thresholds. The main findings show that traditional speed-based data increased as pitch dimensions were increased ( p = 0.002; d = 4.53 ± 0.46; very large). Furthermore, as relative player area increased there was an increase in estimated energy expenditure ( p = 0.004; d = 2. 16 ± 0.20; very large) and average metabolic power metrics ( p = 0.002; d = 1.13 ± 0.46; moderate). Distances covered at metabolic power categories (TP) increased with small-sided games pitch dimension ( p = 0.002; d = 0.3 ± 0.06; small). The study enables coaches to better understand the physical demands imposed on players during specific hurling small-sided games pitch dimensions, and highlights that traditional speed-based data underestimate the running demands of small-sided games.

Contribution of Somesthetic Information to the Perception of Body Orientation in the Pitch Dimension

This study investigated the contribution of otolithic and somesthetic inputs in the perception of body orientation when pitching at very slow velocities. In Experiment 1, the subjects’ task was to indicate their subjective postural vertical, in two different conditions of body restriction, starting from different angles of body tilt. In the “strapped” condition, subjects were attached onto a platform by means of large straps. In the “body cast” condition, subjects were completely immobilized in a depressurized system, which attenuates gravity-based somesthetic cues. Results showed that the condition of body restriction and the initial tilt largely influenced the subjective postural vertical. In Experiment 2, subjects were displaced from a vertical position and had to detect the direction of body tilts. Results showed that the threshold for the perception of body tilt was higher when subjects were immobilized in the body cast and when they were tilted backward. Experiment 3 replicated the same protocol from a supine starting position. Compared to results of Experiment 2, the threshold for the perception of body tilt decreased significantly. Overall, these data suggested that gravity-based somesthetic cues are more informative than otolithic cues for the perception of a quasi-static body orientation.

Effects of gymnastics expertise on the perception of body orientation in the pitch dimension

The purpose of this study was to investigate how experts in motor skills requiring a fine postural control perceive their body orientation with few gravity based sensory cues. In Experiment 1, expert gymnasts and controls had to detect their body tilt when pitching at a velocity of 0.05 deg . s − 1 , in two conditions of body restriction (strapped and body cast altering the somatosensory cues). Contrary to the experts, the controls exhibited a larger body tilt when totally restrained in the body cast. In Experiment 2, subjects had to estimate their Subjective Postural Vertical (SPV) starting from different angles of pitch tilt. The controls exhibited significant errors of SPV judgement whereas the experts were very precise. These results suggest that 1) somatosensory cues are more informative than otolithic cues for the perception of body orientation, and 2) the efficiency of otolithic and/or interoceptive inputs can be improved through a specific training to compensate for the lack of somatosensory cues.

The Effect of Environmental Pitch on Perceived Optic Slant and Eye Level: Lines vs Dots

Visually perceived eye level (VPEL) has been shown to be strongly affected by the pitch of the visible environment (Stoper and Cohen, 1989 Perception & Psychophysics46 469 – 475), even if this environment consists of only two luminous lines pitched from the vertical (Matin and Li, 1992 Journal of Experimental Psychology: Human Perception and Performance18 257 – 289). Here, two luminous vertical lines or 32 randomly distributed luminous dots were mounted on a plane that was viewed monocularly and was pitched (slanted in the pitch dimension) 30° forward or backward from the vertical. In addition to measuring the VPEL, we measured the perceived optic slant (rather than the perceived geographic slant) of this plane by requiring each of our ten subjects to set a target to the visually perceived near point (VPNP) of the plane. We found that, for the lines, VPNP shifted 50% and VPEL shifted 26% of the physical pitch of the plane. For the dots, VPNP shifted 28% but VPEL shifted only 8%. The effect of the dots on VPEL was weaker than might have been predicted by their effect on VPNP, which was used to indicate perceived optic slant. The weakness of the effect of the dots on VPEL implies that changes in VPEL result from a direct effect of the stimuli on VPEL, rather than one mediated by the perceived optic slant of the plane. The non-zero effect of the dots shows that pitched from vertical line segments are not necessary to shift VPEL.